The present invention relates to a keyboard for entering alphanumeric information, and more particularly to a keyboard having one or more rows of keys which extend vertically to a raised position which is higher than the preceding row.
Keyboards are used to input alphanumeric information into electronic devices including computers. Typical keyboards include a fairly standardized arrangement of several rows of keys, each key representing a letter, number, control character such as tabs, spaces, backspaces, etc and an enter key often used to enter a carriage return. Function keys are often used to provide control functions to the electronic device and can be labeled F1, F2, etc.
Keyboard keys are typically moved between a home position and a struck position when used to enter information. In the home position, the keyboard key is usually disposed at the highest vertical extension. To enter the symbol or control function associated with that key, the key is struck or depressed by the user and the key moves downwards from the home position to the struck position. Upon reaching the struck position, a signal is sent to the electronic device indicating that the key has been struck. Keyboard keys are biased, often by a spring, to return to the home position after being struck so that they are ready to be struck again.
Some stationary keyboards, that is, keyboards that are not adapted for mobility, have keys arranged in rows that are not co-planar. As shown in FIG. 1, these keyboards 10 have keys 12 arranged in rows 14a-14n, which are tiered so that each row is not co-planar with the other rows. Some keyboards have a sequentially tiered configuration in which each row is higher than the row immediately in front of it. A tiered row arrangement, especially a sequentially tiered row arrangement can provide improved ergonomics, enabling a user to strike the keys 12 easier and faster, and reducing mistakes and fatigue.
However, portable keyboards, such as keyboards used with portable electronic devices are often covered, or folded when the device is not in use. For example, as shown in FIG. 2, portable computers 16 usually have a display screen 18 which folds over the keyboard 19 providing a space efficient outer cover protecting the keyboard from damage. These portable electronic devices typically have keyboards with keys arranged in rows which are co-planar with each other and thus do not provide ergonomic benefits of the tiered keyboards mentioned above. It is desirable to provide a tiered keyboard for a portable electronic device that is space efficient and can be covered for protection.
According to the present invention, a keyboard is provide having a plurality of vertically extendable rows of keys.
In accordance with one aspect of the present invention, the keyboard includes keys arranged in a plurality of rows. The keyboard has a retracted configuration wherein the rows are generally coplanar with each other and an extended configuration wherein at least some of the rows of keys in the home position are extended from the retracted configuration such that the rows are not coplanar with other rows.
In accordance with a second aspect of the invention, the rows are sequentially tiered in the extended configuration such that each row is higher than the preceding row moving from the front row to the back row.
In accordance with another aspect of the invention, the keyboard includes lifters for lifting the rows of keys to the extended configuration.
In accordance with yet another aspect of the invention, the keyboard is part of an electronic device such as a portable computer.
The advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.